Conveyer drive for loading machines



.1. L. CLARKSON Feb. 1, 1944.

Filed Dec. 22, 1942 CONVEYER DRIVE FOR LOADING MACHINES 2 Sheets-Sheet 2 ZNVENTOR;

JOHN L. CLARKSON BY v W ATTORNEYS Patented Feb. 1, 1944 UNITED STATES PATENT OFFICE Application December 22, 1942, Serial No. 469,853

' (c1. 19s 2os) 8 Claims.

This invention pertains to loading machines, suchas are used in coal mines for loading coal on to mine cars, and particularly to machines designed for use in low entries. More specifically, the invention pertains to a conveyer drive for such a loading machine.

Where coal loading machines have been used to mine coal which occurs in low veins, many difilculties of construction have been encountered on account of the restriction in vertical space available for the machine. The organization of such a loading machine is usually such that the material is gathered from in front of the machine and elevated by a conveyer to pass over the machine to the rear thereof. A delivery conveyer extends beyond the rear of the machine and over the front wall of a mine car, so as to carry the material to the rear of the machine and deposit it inthe car. It is usually desirable to have the delivery conveyer adjustable vertically to accommodate different heights of mine cars, and to take advantage of all the vertical space available in' entries of different heights. However, when the lowest coal veins are encountered, the conveyer must be lowered accordingly. As the movable conveyer structure must carry certain mechanisms among which is a drive mechanism for driving the conveyer chain, the vertical space occupied by any such mechanism must be reduced to a minimum in order to meet the space restrictions imposed by low coal.

In accordance with this invention, an improved drive for the conveyer chain is provided which is organized to occupy a minimum vertical space.

, An important objectof the invention, therefore, is to provide a conveyer drive which will not only occupy a minimum vertical space, but which will have ample power and a positive driving engagement with the conveyer chain.

A further object of the invention is to provide such a drive, which will be simple inv construction and rugged in service.

Further objects will appear from the following description taken in connection with the accompanying drawings in which Figure 1 is a side view of a part of a loading machine embodying this invention showing a portion of the delivery conveyer including I driving means embodyin this invention. Figure 2 is a section one line 2-2 of Figure 1, and Figure 3 is an enlarged section taken on line 33 of Figure 2. Figure 4 is a section on line 4-4 of Figure 3.

Referring to the drawings; I indicates generally the delivery conveyer of a loading machine. In the machine illustrated in Figure '1, the conveyer I is pivoted about at 2 on the chassis of the machine indicated at 3, the chassis itself not being shown. The conveyer I may be of any suitable structure and means are usually provided for raising and lowering the conveyer on its hinge at 2. These devices are not shown in the drawings as they form no part of the present invention.

The conveyer I usually includes a bed or bottom plate 4 over which a conveyer chain 5 is arranged to move. The chain 5 is usually provided with transverse flights 6 extending across the bed 4, and adapted to carry the material along that bed as the chain moves therealong. The movement of the chain is in a direction to the rear of the machine, so as to carry the material to cars placed behind it. In Figure 1 the movement is toward the left for the upper run of the chain upon the bed 4. At the rear end of the conveyer I, the chain passes around a pulley or roller and then returns underneath the bed to the front end Where it passes around a similar pulley or roller. Thus, the chain is endless and when driven moves continually along the bed 4.

' In accordance with this invention, driving means are arranged to engage the return run of the conveyer chain below the bed 4. In the embodiment illustrated two drive shafts I and 8 are arranged below the bed 4 and extending transversely thereof. These shafts are journaled in suitable bearings in side plates 9 on the conveyer I and extending below the bed 4. These shafts are positioned at a point of the conveyer where the return run of the chain 5 may be straight along the underface of the bed 4. In the embodiment illustrated the conveyer has a single chain in the middle thereof and the flights 6 extend laterally in both directions therefrom. The invention may, however, be applied to other types of conveyers, including those having two chains, one at each side of the bed 4 with the flights extending therebetween. Each of the shafts I and 8 carries a small sprocket designated for the shafts I and 8, respectively. These are also small sprockets preferably smaller than the sprockets ID and II. They are connected together by a chain It, which provides the driving connection between them. As the chain M may be long enough to slip over the teeth of one sprocket while engaged with the other, in order to put the chain on the sprockets, means for maintaining this chain taut are provided by a roller 55 on a stub shaft l6 suitably mounted on the plate 9. Ihis lroller may be .0f .such a size as to ke'ep the 'ehain Ill sufficiently *tautto maintain a fixed timing between the teeth of the sprockets I9 and l I. These sprockets are 7 mounted on the shafts I and 8 in such relative positions that their teeth .nngagethechain 25' in staggered relation with each other. .By this is meant that a tooth of one of these sprockets' or leaving engagement with the chain. These relative positions-areillustrated-inFigure,3. This timing relation i-islsuch, as to i insure that ,there --w-ill-:al-ways be fulli-drivingeengagement oilthe chainwith-either oneorthe other of ,the sprockets ligand =1 l.

-As the sprockets U) and [Lengagethe chain S ata positionon the .conveyer -=l, where said chain has a substantially straight run, it is-desimple to providemeansto insure-egainst-any possibility of the chain iumpingLQVer ,the :teeth ofi-the sprockets. Fonthis purpose a backing shoe :or: rail I1 is secured-to the :underside. of the bed Lin-any suitablamanner as by means of rivets L8. .In the embodiment. shown .thetshoe H has the flormiofta-straight strip or narrow plate secured to the .bed 4 ,and positioned-directly over the-pathioi the chain-5v The'width of the shoe 1;! is preferably suchthat .it will passbetween thees ide flanges of the links of the chain 5, as :shownimEigureZ. By this arrangement the :shoeiserves ase :guide to maintaintherchain latorally min :a rstraight :run -.properly aligned with ,thesprockets l9 ,and H. The shoe, therefore, is placed not only in a zlaterallyeguiding relation to the chain, but dnasbacking orretaining relation, such as-zto prevent; any tendency for the chain to ride rover the teeth of the driving sprockets.

Theshaftslandm, with their sprockets l9 :and .-l l,,-thus operateito i drive .the .conveyenchain .5. This drive isitself-drivenirom-suitable power means, not shown, -.located.on the loader chassis, through .the agency of driving connections, .inncluding a telescoping shaft 88 universally jointed at both ends, a short shaft 20. and ;gearing.2i

of any suitable-type which includes .a gear 22 on one :of the shafts l v :or 8, in the embodiment illustrated on theshaftil'. Thedriving effort is thus delivered-to the shaft 1' .and .by: iit, -through the chain lA-to :the shaft :8. Accordingly, both shaftsql and 8 are: active ,indriving the chain 5. iit'wwillbezseenethat this invention provides :drive' which is simple and effective for driving the {conveyer chain. "By placingiboth theshafts andw'8 closelygadjacent the bed-4 and providing ,smallesprockets ill and 1 VI the drive is reduced tciminimum vertical dimensions consistent with strength. While ordinarily a small sprocket, such .zas-Hi, would :not be, practical. for driving a chainwhyengaging qa straieht run thereof, for the reason thatqat certain points. in its revolurtioh the engagement of. the teeth with the chain .z-may zbe uncertain, by-the provision V of. a plurality :of isuch sprocketswith their teeth arranged in staggered relatihnand driven in unison, a positive drive is assured. This arrangement of a plurality of small sprockets, engaging the chain at a straight run thereof, eliminates the usual bend in the chain to pass it around the driving sprocket with an idler to keep it in engagement with the sprocket, which has been the usual driving arrangement heretofore. Accordingly, not only the uncertain driving engagement of this looped arrangement is avoided, but the vertical ispacecoccupied itherebyisagreatly .:reduced. The provision :of the backing ishoe I! aeliminates the only uncertainty encountered in a drive in which a sprocket engages a straight run of the chain, namely, the danger of the chain jumping over the teeth *of *the sprocket. This shoe not only guidesthechain surely into correct engagement with the sprockets, but maintains it in proper driving engagement"throughout that part of its runzduring which it is engaged with the driving sprockets.

While a preferred embodiment-oiitherinvention has 'loeen illustratedinithe :drawings, :it'-will be understood that ivarious changes :may be anade in the" details "of rconstruction'fwithin thescope "of theappended claims withoutrdepartingirom the spirit of this invention,zaindfitrisrundersttaod, therefore, :that the invention his not limited to the specific details:-shownwandxdescribed.

Havingithus described Ethe :invention, what is claimed is:

1. .In a loading .machine of :the character described idesignedito ?operate: in low 'entries having a conveyerincluding a'conveyertbedand a'fleiiible "chain moval'ale ftherealong a conveyer drive :coniprisin g,'ameans providin'gta substantially straight rruni'for said chainiialong and 'belowisaid bed,"a plurality of drive shadts closelya'dj'acent said chain at said-straight runpsinall sproc'kets on said shetftsthaiiing:teethmeshingwith said chain in staggered .r'elation'zto aeach other, ;other small sprockets onrsaid:shafts,iratdriving'chaintconnectingsaidtother sprockets to zdrive oneaat the same speed andin "titer-same :direction =of rotation as the ':other,;means :for maintaining said last chain taut, andineans. associated with :sa'id bed adapted to retaincsaid iiirstr'shainin driving engagement with said :first :sproekets.

2. :In1a loading ;machine'='of the'character described :designed to operatezinilow entries having ,a conveyer includingazconvey'enbed anda flexible chain movable therealong, a conveyer drive-comprising,imeans'provi'ding a substantially straight run 'for said chainelong and :below said bed, a plurality :of :drive shafts closely adjacent said chain at said straight =run, driving 'means arranged to drive said shafts in the same direction of rotation, small sprockets on sa'ids'haftshaving teeth meshing with said chain, and a backing shoe on said bed extending along "said straight run in laterally-guiding relation to said chain and positioned to "retain said chain in driving engagement with said sprockets.

3. In a'loading machine of the character def? scribed designed to 'operateinlow entries'having a conveyer including aconveyer bed and a'fiexible chain movable thereal'ong, aconveyer" drive comprising,'means providing asubstantially straight run for said chain alongand below said bed, a plurality of drive shafts closely adjacent-said chain at saidzstraight-"run, "driving means arranged to drive said shafts in the same direction of rotation, small sprockets onsaid" shafts'hav'ing teeth meshing with said chain,'and a backing shoe on said he'd extending along said straight run adapted to retain said chain in driving gagement with said sprockets.

4. In a loading machine of the character described designed to operate in low entries having a conveyer including a conveyer bed and a flexible chain movable therealong, a conveyer drive comprising, means providing a substantially straight run for said chain along and below said bed, a plurality of drive shafts closely adjacent said chain at said straight run, driving means arranged to drive said shafts in the same direction of rotation, small sprockets on said shafts having teeth meshing with said chain, and means associated with said bed providing a backing for said chain to retain the same in driving engagement with said sprockets.

5. In a loading machine of the character described designed to operate in low entries having a conveyer including a conveyer bed and a flexible chain mnvable therealong, a conveyer drive comprising, means providing a substantially straight run for said chain along and below said bed, a plurality of drive shafts closely adjacent said chain at said straight run, driving means arranged to drive said shafts in the same direction of rotation, small sprockets on said shafts having teeth meshing with said chain, and means associated with said bed adapted to retain said chain in driving engagement with said sprockets.

6. In a loading machine of the character described designed to operate in low entries having a conveyer including a flexible chain, a conveyer drive comprising, means providing a substantially straight run from said chain, a plurality of drive shafts closely adjacent said chain at said straight run, driving means arranged to drive said shafts in the same direction of rotation and at the same speed, small sprockets on said shafts having teeth meshing with said chain but in staggered relation to each other, and backing means to retain said chain in driving engagement with said sprockets.

7. In a loading machine of the character described designed to operate in low entries having a conveyer including a flexible chain, a conveyer drive comprising, means providing a substantially straight run for said chain, a plurality of drive shafts closely adjacent said chain at said straight run, driving means arranged to drive said shafts in the same direction of rotation and at the same speed, and small sprockets on said shafts having teeth meshing with said chain but in staggered relation to each other.

8. In a loading machine of the character described designed to operate in low entries having a conveyer including a flexible chain, a conveyer drive comprising, means providing a substantially straight run for said chain, a plurality of drive shafts closely adjacent said chain at said straight run, driving means arranged to drive said shafts in the same direction of rotation, and small sprockets on said shafts having teeth meshing with said chain.

JOHN L. CLARKSON. 

